When large volumes of data (e.g. hundreds of Gb or more than 1 Tb) are collected, methods for analysing and displaying the data can be used to assist a user in finding and/or reviewing desired data. For example, a dataset might include several thousands or hundreds of thousands of Radio Frequency, RF, spectrum measurements. Suitable methods can include pre-processing, index building, and hierarchical searching.
For example, U.S. Pat. No. 8,078,394 B2 describes processing Global Positioning System, GPS, data into a track of spatially-partitioned segments such that each segment has a cell. Each cell has an associated temporal index into which data for the segments of the cell are inserted.
In another example, G. Noël et. al. “The Po-tree: a Real-time Spatiotemporal Data Indexing Structure”, Developments in Spatial Data Handling 2005, pp 259-270, 11th International Symposium on Spatial Data Handling, describes indexing measurement data from sensors using a KD tree index for the sensor locations, with spatial nodes corresponding to each sensor linked to a modified B+ tree time index structure for measurements from that sensor.